| 摘要 |
A roof truss is provided comprising a bottom chord, a first top chord, and a second top chord forming a triangle with an apex at a distance A above the bottom chord. At least a web member is disposed between the top chords and the bottom chord such that, in a first state of operation, the at least a web member is capable of transmitting at least one of a tension force and a compression force between the top chords and the bottom chord. The roof truss further comprises at least an expandable interface for expandable interfacing at least one of the at least a web member with one of the chords for enabling, in a second state of operation, expansion of the distance A to an extent that uplift of the bottom chord is substantially reduced. |
